GENCHEM CH 1 VOCAB

Chemistry

The study of matter

Matter

Anything that has mass and takes up space

Chemistry

The study of matter

Matter

Anything that has mass and takes up space

Substance

A specific type of matter with a fixed composition and characteristic properties

Elements

Simplest types of substances

Plasma

A gaseous state with electrically charged particles.

Compounds

Made of two or more elements

Elements and Compounds

Two types of substances

Mixture

Combination of two or more substances

Homogenous mixture or Solution

Mixture with a constant composition throughout, CLEAR

Heterogeneous Mixture

Mixture without a constant composition, CLOUDY

Scientific Method

A systematic approach used by scientists to investigate questions, build knowledge, and develop explanations for natural phenomena

Scientific Law

A statement that describes a consistent, observable relationship or rule in nature

Hypothesis

Educated guess

Theory

Attempts to explain the laws of the natural world (the why and how)

Mass

A measure of how much matter is in a given object

Weight

Measure of the force of gravity between two objects

Density

Amount of mass per volume.

Extensive property

Varies with amount (ex: mass and volume)

Intensive property

Amount does not change (independent) (ex: density, melting or freezing points)

Physical property or physical change

Measured without changing the identity (ex: mass, boiling)

Chemical property or Chemical change

Require an identity change in order to measure (ex: flammability, rust)

Accuracy

How close a measurement is to a known or accepted value

Precision

How close repeated measures are to one another

Significant Figures

Digits in a measurement or calculation that have the highest degree of certainty

Exact

Numbers that are known to be ______ have unlimited SFs

Significant

All nonzero numbers are _____

Significant

Zeros between two nonzero numbers are _____. (0.0309) the 0 between the 3 and 9

Not Significant

Leading zeros are _____. (Left of the first nonzero #)

Significant

Trailing zeros after a decimal are _____. (23.000 = 5?)

Significant if there is a decimal at the end.

Trailing zeros before decimal spot are ____.

Not Significant (even the 10)

Exponent numbers are _____.

Significant Figures

For multiplication and division, your answer will be rounded to match the figure with the least amount of _____.

Decimal Places

For addition and subtraction, your answer will be rounded to match the figure with the least amount of _____.

Système International

SI stands for _____.

Scientific Notation (or standard index form)

Way of expressing numbers that are too small or large to be conveniently written in decimal form. It would require writing out an inconveniently long string of digits.

Measurements

Quantification of attributes of an object/event, used to compare with other o/es

°C + 273.15 (Kelvin has no °)

Celsius to Kelvin

°F = 1.8(C) + 32

Celsius to Farenheit

°C = 5/9[°F-32]

Fahrenheit to Celsius

Have to do F→C→K. °C = 5/9[°F-32] then K = °C + 273.15 (Kelvin has no °)

Fahrenheit to Kelvin

Dimensional Analysis

Analysis of relationships btwn diff physical qtys by IDing their base qtys and units of msmnt and tracking those dimensions as calculations or comparisons are formed

Conversion Factor

Relationship between units that is used to change the units of a measured quantity without changing the value

Conversion Ratio

Numerator and denominator have same value expressed in different units (always equals 1)

Dimensional Homogenity

Only quantities with the same dimensions can be added, subtracted, equated or compared

Absolute Scale

Measured with absolute zero

Relative Scale

Measured against some agreed upon point of reference

Heat

Quantitive measure of energy

Temperature

Relative measure of how hot or cold something is

Does Not

If something is hotter, that means it DOES/DOES NOT have more heat

Does Not

Kelvin DOES/DOES NOT have negative temperatures

Kilo Hecto Deka base Deci Centi Milli

Kittens have dreams of drinking cold milk

2.54

1 inch = _____ cm

0.9144

1 yard = _____ meters

1.609

1 mile = _____ kilometers

28.35

1 ounce = _____ grams

453.6

1 pound = _____ grams

473.2

1 pint = _____ milliliters

3.785

1 gallon = _____ liters

1

1 milliliter = _____ cm³

Physical

Freezing is a _____ change

Chemical

Burning is always a _____ change

Physical

Condensation/vaporizing is a _____ change

Chemical

Corrosion/rust is a _____ change

3

206 has _____ SFs

1

3,000 has _____ SFs

5

2.0030 has _____ SFs

3

9.04 × 10⁵ has _____ SFs

4

0.007008 has _____ SFs

4

89,040 has _____ SFs

2

0.0000021 has _____ SFs